1. Field of the Invention
The present invention relates generally to obstetrical instruments and more particularly to a device for simultaneously cutting and clamping an umbilical cord and to clips for use in combination with the device.
2. Brief Description of the Prior Art
Complications occur in approximately five percent of the hospital deliveries of infants. Such complications can include having the umbilical cord wrapped around the baby's neck. In this difficult moment the baby is struggling to breathe, and the doctor is attempting to cut and clamp the umbilical cord. The cutting and clamping of the umbilical cord as soon as possible in these situations is an important factor for the life of the newborn, and the prevention of brain damage secondary to hypoxia. The conventional technique is to use clamps on the umbilical cord, and to cut between them with scissors. However, this technique wastes valuable time at a critical point in the delivery of the newborn. There is a need for a device that would save valuable time and reduce bleeding and infection such as AIDS or hepatitis.
Surgical instruments for simultaneously severing and clamping the umbilical cord of a newborn infant are known. For example, U.S. Pat. Nos. 640,517, 2,052,870, 2,060,724, 3,166,071, and 4,428,374 each disclose clamping devices for simultaneously cutting the umbilical cord and clamping both the maternal and the fetal ends of the severed cord. The devices generally employ a pair of clamps that are detachable or removal from the clamping device after the cord has been severed or clamped.
U.S. Pat. No. 3,631,858 discloses a device for simultaneously clamping and severing the umbilical cord in a single operation requiring only one hand, no detachable clamps being employed. U.S. Pat. No. 4,648,401 discloses a scissors like surgical instrument for severing an umbilical cord employing a single umbilical cord clamp and a single use, disposable blade assembly to separate the cord. The instrument permits the release of the clamp or the hemostat on the maternal end of the umbilical cord immediately after the cord is cut for collection of a blood specimen for fetal Rh factor screen test to avoid discomforting the infant by obtaining the specimen directly from the infant.
The prior art devices generally share a common disadvantage in that they are adapted for use in severing and clamping umbilical cords having a relatively small diameter. However, in obstetrical practice the range in diameter of the umbilical cords encountered is substantial (e.g. about 1-2.5 cm). Thus, the prior art devices are generally not suitable for severing in clamping cords having relatively large parameters. Umbilical cords include tough, gelatinous, fibrous tissue, as well as two arteries and one vein, and successful devices must provide sufficient force to cleanly severe them. An example of a prior art device adapted to exert substantial force for severing large umbilical cords is disclosed in my U.S. Pat. Nos. 4,870,965 and 5,009,657.
A further disadvantage of some prior art devices is that they may not securely grip on the surface of the umbilical cord. The umbilical cord of the newborn infant has a very slippery surface. Because it is covered with Wharton's jelly, a jelly-like substance, the cord is slippery and consequently very difficult to grasp and cut. Thus, when a conventional scissors-like device is closed upon the surface of the cord, the cord may be pushed out from between the blades of the device.
Some prior art devices provide teeth on both the upper and lower surfaces of the clamping jaws to securely hold the umbilical cord while the cord is being cut. Alternatively, it is known to provide teeth on both the upper and lower arms of detachable clips, and to securely hold such clips within the cutting and clamping device while the cord is being cut. The teeth immobilize the cord in place while it is being cut. Nevertheless, substantial force is required to sever a cord immobilized in this way.
There is a continuing need for an umbilical cord cutting and clamping device which can be used to quickly, easily and securely cut and clamp the full range of cords encountered in obstetrical practice.